The plants look waterlogged; the roots need air to breathe.
Drain the water back into the reservoir (use a simple filter to prevent damage to the pump) and just use a schedule for watering.
I used a mechanical timer switch for 15 mins every hour for my hyrdo setup. For soil, such tiny plants, and no lights you would need far less frequency. A general rule of thumb is to give it enough time between waterings to let it get a bit dry.
Drain the water back into the reservoir (use a simple filter to prevent damage to the pump) and just use a schedule for watering.
I used a mechanical timer switch for 15 mins every hour for my hyrdo setup. For soil, such tiny plants, and no lights you would need far less frequency. A general rule of thumb is to give it enough time between waterings to let it get a bit dry.